re PR c++/39639 (no diagnostic for ill-formed pack expansion)

2009-04-22  Dodji Seketeli  <dodji@redhat.com>

    gcc/cp/ChangeLog:
    	PR c++/39639
    	* parser.c (cp_parser_template_argument_list): Display an error
    	when an ellipsis is not preceded by a parameter pack. Also, warn
    	about variadic templates usage without -std=c++0x.
    
    gcc/testsuite/ChangeLog:
    	PR c++/39639
    	* g++.dg/cpp0x/pr39639.C: New test.

From-SVN: r146610

gcc/cp/ChangeLog

+2009-04-22  Dodji Seketeli  <dodji@redhat.com>
+
+	PR c++/39639
+	* parser.c (cp_parser_template_argument_list): Display an error
+	when an ellipsis is not preceded by a parameter pack. Also, warn
+	about variadic templates usage without -std=c++0x.
+
 2009-04-21  Taras Glek <tglek@mozilla.com>
 
 	* cp-tree.h: Update GTY annotations to new syntax.

gcc/cp/parser.c

@@ -10470,6 +10470,12 @@ cp_parser_template_argument_list (cp_parser* parser)
          argument pack. */
       if (cp_lexer_next_token_is (parser->lexer, CPP_ELLIPSIS))
         {
+	  if (argument == error_mark_node)
+	    {
+	      cp_token *token = cp_lexer_peek_token (parser->lexer);
+	      error ("%Hexpected parameter pack before %<...%>",
+		     &token->location);
+	    }
           /* Consume the `...' token. */
           cp_lexer_consume_token (parser->lexer);
 

gcc/testsuite/ChangeLog

+2009-04-22  Dodji Seketeli  <dodji@redhat.com>
+
+	PR c++/39639
+	* g++.dg/cpp0x/pr39639.C: New test.
+
 2009-04-22  Mark Heffernan  <meheff@google.com>
 
        * gcc.dg/profile-generate-3.c: New test.

gcc/testsuite/g++.dg/cpp0x/pr39639.C

+// Contributed by Dodji Seketeli <dodji@redhat.com>
+// Origin: PR c++/39639
+// { dg-options "-std=c++0x" }
+// { dg-do "compile" }
+
+template <class... Types>
+struct S
+  : S<...Types>, // { dg-error "expected parameter pack before '...'" }
+    S<...Types...>, // { dg-error "expected parameter pack before '...'" }
+    S<...> // { dg-error "expected parameter pack before '...'" }
+{
+  static int f () { return 1;}
+};
+
+int
+main ()
+{
+  return S<void>::f ();
+}
+